[RFC] ASoC: soc-core: proposal to remove num_auto_selectable_formats from snd_soc_dai_ops

[RFC] ASoC: soc-core: proposal to remove num_auto_selectable_formats from snd_soc_dai_ops

[HariKrishna Sagala]

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Hi,

Good day.
I’d like to propose a small cleanup and simplification in the
snd_soc_dai_ops structure by removing the
"num_auto_selectable_formats" parameter.

Context:
Currently,snd_soc_dai_ops includes the "num_auto_selectable_formats"
field to indicate the number of entries in the "auto_selectable_formats"
array.However, this count can be derived programmatically using the
ARRAY_SIZE() macro wherever needed.

Proposal:
Remove the "num_auto_selectable_formats" field from the
snd_soc_dai_ops structure.Replace usage references to this field with
ARRAY_SIZE(auto_selectable_formats) in the relevant code paths.

One effect I see is if the parameter "auto_selectable_formats" has
only one priority format because few codecs are defined as a u64
variable,will correct and prepare a patch.

Please provide suggestions, objections and also to consider any
compatibility problems,historic importance of same.

If there are no objections, I would like to prepare a patch for
the same.

Thanks.

Regards,
HariKrishna.

Re: [RFC] ASoC: soc-core: proposal to remove num_auto_selectable_formats from snd_soc_dai_ops

[Kuninori Morimoto]

Hi HariKrishna

Thank you for suggestion

> Iʼd like to propose a small cleanup and simplification in the
> snd_soc_dai_ops structure by removing the
> "num_auto_selectable_formats" parameter.

Do you mean like this ?

	struct snd_soc_dai_ops {
		...
		const u64 *auto_selectable_formats;
	-	int num_auto_selectable_formats;
		...
	};

> Currently,snd_soc_dai_ops includes the "num_auto_selectable_formats"
> field to indicate the number of entries in the "auto_selectable_formats"
> array.However, this count can be derived programmatically using the
> ARRAY_SIZE() macro wherever needed.

If my understanding was correct, unfortunately we can't do it.

We can use ARRAY_SIZE() in each driver, because we can access to raw array.
But can't use it on ASoC framework, becase auto_selectable_formats is just
a pointer. see how ARRAY_SIZE() is defined.

	--- driver ---
	my_formats[] = {
		[0] = SND_SOC_POSSIBLE_DAIFMT_xxx | SND_SOC_POSSIBLE_DAIFMT_xxx ...,
		[1] = SND_SOC_POSSIBLE_DAIFMT_xxx | SND_SOC_POSSIBLE_DAIFMT_xxx ...,
	};

	// We can use ARRAY_SIZE() in driver, because we know raw array.
	my_dai_ops = {
		...
		.auto_selectable_formats	= my_formats,
=>		.num_auto_selectable_formats	= ARRAY_SIZE(my_formats),
	};

	--- soc-xxx.c ---
	// it will be error, because we don't know its size
=>	int num = ARRAY_SIZE(ops->auto_selectable_formats);

Or do you mean create new macro, like this ?

	#define ASOC_SELECT_FORMATS(array)\
		.auto_selectable_formats	= array,
		.num_auto_selectable_formats	= ARRAY_SIZE(array)

	my_ops = {
		...
	-	.auto_selectable_formats	= my_formats,
	-	.num_auto_selectable_formats	= ARRAY_SIZE(my_formats),
	+	ASOC_SELECT_FORMATS(my_formats),
	};

Or am I misunderstanding your suggestion ?


Thank you for your help !!

Best regards
---
Kuninori Morimoto

Re: [RFC] ASoC: soc-core: proposal to remove num_auto_selectable_formats from snd_soc_dai_ops

[harikrishna]

On Fri, Oct 31, 2025 at 12:28 PM Kuninori Morimoto
<kuninori.morimoto.gx@renesas.com> wrote:
>
>
> Hi HariKrishna
>
> Thank you for suggestion
>
> > Iʼd like to propose a small cleanup and simplification in the
> > snd_soc_dai_ops structure by removing the
> > "num_auto_selectable_formats" parameter.
>
> Do you mean like this ?
>
>         struct snd_soc_dai_ops {
>                 ...
>                 const u64 *auto_selectable_formats;
>         -       int num_auto_selectable_formats;
>                 ...
>         };
>
> > Currently,snd_soc_dai_ops includes the "num_auto_selectable_formats"
> > field to indicate the number of entries in the "auto_selectable_formats"
> > array.However, this count can be derived programmatically using the
> > ARRAY_SIZE() macro wherever needed.
>
> If my understanding was correct, unfortunately we can't do it.
>
> We can use ARRAY_SIZE() in each driver, because we can access to raw array.
> But can't use it on ASoC framework, becase auto_selectable_formats is just
> a pointer. see how ARRAY_SIZE() is defined.
>
>         --- driver ---
>         my_formats[] = {
>                 [0] = SND_SOC_POSSIBLE_DAIFMT_xxx | SND_SOC_POSSIBLE_DAIFMT_xxx ...,
>                 [1] = SND_SOC_POSSIBLE_DAIFMT_xxx | SND_SOC_POSSIBLE_DAIFMT_xxx ...,
>         };
>
>         // We can use ARRAY_SIZE() in driver, because we know raw array.
>         my_dai_ops = {
>                 ...
>                 .auto_selectable_formats        = my_formats,
> =>              .num_auto_selectable_formats    = ARRAY_SIZE(my_formats),
>         };
>
>         --- soc-xxx.c ---
>         // it will be error, because we don't know its size
> =>      int num = ARRAY_SIZE(ops->auto_selectable_formats);
>
> Or do you mean create new macro, like this ?
>
>         #define ASOC_SELECT_FORMATS(array)\
>                 .auto_selectable_formats        = array,
>                 .num_auto_selectable_formats    = ARRAY_SIZE(array)
>
>         my_ops = {
>                 ...
>         -       .auto_selectable_formats        = my_formats,
>         -       .num_auto_selectable_formats    = ARRAY_SIZE(my_formats),
>         +       ASOC_SELECT_FORMATS(my_formats),
>         };
>
> Or am I misunderstanding your suggestion ?
>
>
> Thank you for your help !!
>
> Best regards
> ---
> Kuninori Morimoto

Hi Kuninori Morimoto,

Yes, you are right.
I have got it now.
We can use it in codec driver not in framework.
Thought of changing the type of "U64 *auto_selectable_formats" to
"U64 (*auto_selectable_formats)[]" and removing the
"num_auto_selectable_formats".
But cannot be used to get count. Apologies for this.

Thanks for the guidance.

Regards,
HariKrishna.